<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <style>
        #app{
            padding-right: 10px;
            width: 300px;
            height: 200px;
            background-color:#f0eeee;
        }
        .cin_item{
            margin: 10px;
            width: 280px;
            height: 80px;
            font-size: 48px;
        }
        .item{
            margin-top: 10px;
            margin-left: 10px;
            width: 50px;
            height: 30px;
            float: left;
            background-color: #c0bebe;
            line-height: 30px;
            font-size: 20px;
            text-align: center;
        }
    </style>
</head>

<body>
    <div id="app">
        <div>
            <input type="text" v-model:value="counter" class="cin_item">
        </div>
        <div class="content">
            <div class="item" @click="counter += 0">0</div>
            <div class="item" @click="counter += 1">1</div>
            <div class="item" @click="counter += 2">2</div>
            <div class="item" @click="counter += 3">3</div>
            <div class="item" @click="counter += 4">4</div>
            <div class="item" @click="counter += 5">5</div>
            <div class="item" @click="counter += 6">6</div>
            <div class="item" @click="counter += 7">7</div>
            <div class="item" @click="counter += 8">8</div>
            <div class="item" @click="counter += 9">9</div>
        </div>
    </div>
</body>
<script>
    const Counter ={
        data() {
            return {
                counter: 0   
            }
        }
    }  

    Vue.createApp(Counter).mount('#app')
</script>

</html>